Alkaline phosphatases in tissues and sera of cats

The numbers and widths of bands of alkaline phosphatase (ALP) activity in polyacrylamide gels and the comparison of their electrophoretic mobility to that of a reference substance (Rf value) were found to be reliable aids in the identificaiton of various isoenzymes in in serum and organ extracts from cats. The hepatic isoenzyme was identified in sera of clinically normal adult cats, pregnant cats late in gestation, and cats with common bile duct occlusion. In addition to the hepatic isoenzyme, placental ALP was found late in gestation in sera from queens. Sera from kittens less than 15 weeks of age contained only the osseous ALP isoenzyme.